1. Field of the Invention
The present invention relates to a wrench assembly for use in combination with a lug wrench for removal of a stud-nut from an outer nut of a double nut assembly used to secure a wheel mount to a hub of the vehicle.
2. Discussion of Prior Art
Dual wheel assemblies are commonly used on trucks to improve tire wear and fuel economy, as well as to reduce vibration and thus provide a smoother ride. The inner and outer wheel mounts of a dual wheel assembly are secured to a circular arrangement of threaded studs of a vehicle's axle hub by a multiple hole, double cap nut mounting system. A double nut assembly is supported by each of the threaded studs, with each double nut assembly including an inner nut and an outer nut. The inner nut, also referred to as a stud-nut, is a square-headed member having an internal threaded bore and external threads, and is threaded onto one of the threaded studs of the axle hub to secure the inner wheel mount. The outer nut is threaded onto the stud-nut to secure the outer wheel mount.
The unique arrangement of the double nut assemblies permits the removal of the wheel assemblies from the vehicle's axle hub using a lug wrench, such as a pneumatic wrench. However, problems often arise in the removal of the stud-nut from the outer nut of the double nut assembly which may be connected to the wheel mount of the outer wheel assembly of the vehicle. That is, water, dirt and salt often cause the outer nut and the nut-stud to become "frozen" which requires special procedures for removal, and thus can lead to potential damage to the wheel mount, as well as the stud-nut and/or outer nut.
To assist in the removal of the stud-nut from the outer nut of the double nut assembly a nut wrench was developed. This prior art nut wrench consists of a wrench body having at one end a hexagonal opening and a perpendicularly extending extension at the opposed end thereof. The hexagonal opening of the body is adapted to be placed about the outer nut of the double nut assembly, and the extension at the opposite end thereof to be placed within a stud-receiving opening in the wheel mount (which does not contain a double nut assembly) or adjacent a portion of a rim of the wheel mount. The nut wrench of the prior art is designed to hold or secure the outer nut of the double nut assembly so as to prevent rotation of the outer nut when a wrench is used to remove the stud-nut therefrom.
The nut wrench of the prior art described above can be highly dangerous to the user. For example, in utilizing the prior art nut wrench the user must hold or press the nut wrench against the wheel mount to maintain the extension member of the wrench within the stud-receiving opening of the wheel mount or adjacent the rim of the wheel mount. Because of the torque generated when pneumatic wrenches are used to remove the stud-nut from the outer nut of the double nut assembly, the user cannot always maintain the prior art wrench in place, resulting in potential injury to the user, damage to the stud-nut of the double nut assembly (such as shearing) and damage to the wheel mount created by rotation of the wrench.
Thus, while the prior art wrench has met with some success, the need still remains for an inexpensive, durable wrench which can be used in combination with a lug wrench, such as a pneumatic wrench, to remove the stud-nut from the outer nut of the double nut assembly without requiring the user to support such wrench against the wheel mount with the user's hand or foot; and which does not inadvertently dislodge from contact with the wheel mount and thereby spin due to torque generated by a pneumatic wrench when a pneumatic wrench is employed to remove the stud-nut from the outer nut of the double nut assembly. It is to such a wrench assembly that the subject invention is directed.